The present biological methods of sewage treatment are very slow depending entirely on the growth of microorganisms and their ability to digest organic matter. The growth of these microorganisms and their digestion ability is dependent on nutritional balance and chemicals in the effluent, and fluctuations can throw the system out of balance causing nonfunction or excessive function. The unpredictability and the slowness of the biological digestive process requires enormous space for holding capacities and large equipment for processing. The ultimate disposal of the sewage sludge is an ever increasing problem. The necessity for a new method of treatment is obvious.
Raw sewage contains a mixture of many kinds of insoluble and soluble solids of organic and inorganic material. The insoluble solids are usually sediments or in suspension. The sediments are mostly inorganic materials such as sand, pebbles, metal particles and also organic materials such as paper, wood, plastics, and the like. The solids in suspension which include colloids, are usually organic material composed of human waste, vegetable matter, oils, grease and the like. The solids in solution are both organic and inorganic containing urine, soaps, salts and other chemicals. Even the water itself which comes from the usual sources such as tap water, wells and rivers, contains from 400 to 800 parts per million (ppm) of total solids. Nearly all of the present processes for handling raw sewage requires minimal treatment of solid waste for disposal purposes and even this is restricted as much as possible to inorganic sediments. All organic suspended solids are treated microbiologically to break down or digest the solid structures to produce soluble chemicals and gases. The solids which are by this means converted into liquid form are fed back into the sewage effluent increasing the total dissolved solids in this liquid.
The federal, state and local government regulations are becoming more stringent regarding the amount of total solids, bacteria and toxics allowed in the effluent as time progresses, and the 1985 standards cannot be met by any of the present systems in operation. The effluent leaving the plant may not have pathogenic microorganisms, and to assure this condition, the effluent is treated with chlorine before release. Chlorine reacts with nitrogen compounds which create chemicals which are extremely toxic to fish and biological life, such as polychlorinated biphenols and amino chlorides which are both toxic and carcinogenic. Potable or drinking water treated with chlorine can form chloroform which is found to be carcinogenic to rats and mice, and the EPA has found chloroform to be present in all United States drinking water supplies.
It should be quite apparent that the present method of raw sewage treatment and the disposal of the effluent does not prevent pollution in the rivers or in the oceans or anywhere the discharge is made, but actually increases the pollution. It appears that the emphasis has been on merely making the visual organic materials disappear from view to the naked eye, and when this has been accomplished, then allowing the transformed liquid to be treated by adding chlorine to destroy the pathogenic organisms which merely create other and additional toxic chemicals which when added to the effluent merely adds to the pollution without removing the actual pollutants.
The treatment of sewage has two facets of great importance. The first is the disposal of a clear effluent without contaminating and destroying biological life cycles. The second is the disposition of the organic sludge resulting from the treatment into a useful by-product.
Because of the now apparent result of the present sewage treatment, it is necessary to accomplish a basic change to the treatment of raw sewage and industrial waste water and its ultimate effluent which would in fact eliminate pollution, make the effluent safe for biological life while at the same time, perhaps, providing a useful by-product for further sustenance of biological plant life on a commercial basis.